Geodesic
Automorphisms of distance-regular graph with intersection array $\{117,80,18,1;1,18,80,117\}$
Sibirskie èlektronnye matematičeskie izvestiâ, Tome 13 (2016), pp. 972-986.

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Distance-regular graph $\Gamma$ with intersection array $\{117, 80, 18, 1; 1, 18, 80, 117\}$ is an $AT4$-graph. Antipodal quotient $\bar \Gamma$ has parameters $(378, 117, 36, 36)$. Both graphs have strongly regular neighbourhoods with parameters $(117, 36, 15, 9)$. In the work automorphisms of the said graphs are found. In particular, there exist graphs of rank 3 with parameters $(117, 36, 15, 9)$ and $(378, 117, 36, 36)$, and graph with intersection array $\{117, 80, 18, 1; 1, 18, 80, 117\}$ is not arc-transitive.
Keywords: strongly regular graph, eigenvalue, automorphism of graph. 
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A. A. Makhnev; D. V. Paduchikh; M. M. Khamgokova. Automorphisms of distance-regular graph with intersection array $\{117,80,18,1;1,18,80,117\}$. Sibirskie èlektronnye matematičeskie izvestiâ, Tome 13 (2016), pp. 972-986. http://geodesic.mathdoc.fr/item/SEMR_2016_13_a29/

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